1. Field of the Invention
The present invention relates to a semiconductor device.
2. Description of the Related Art
In semiconductor devices, it is known to provide an ESD (Electro Static Discharge) protection circuit between a power supply terminal (VDD) and a ground terminal (VSS).
For example, the semiconductor device may be provided with the ESD protection circuit that is surrounded by a guard ring connected to a ground wiring, as proposed in Japanese Laid-Open Patent Publications No. 2012-043845 and No. 2014-154595, for example.
Due to recent size reduction of the semiconductor devices, deteriorated reliability of metal wirings caused by EM (Electro-Migration) is becoming a problem. Because the EM is a phenomenon that occurs when a current flows through the metal wiring, the EM may be generated in the metal wiring when an ESD current flows through the metal wiring. However, the existing semiconductor devices provided with the ESD protection circuit do not take into consideration the generation of EM.